1. Field of the Invention
The invention generally relates to a substrate and manufacturing method thereof. More particularly, the invention relates to a circuit board and manufacturing method thereof.
2. Description of Related Art
With integrated circuit (IC) packaging technology, wire bonding or flip chip bonding are typical methods for electrically connecting chips and circuit boards. Taking the flip chip bonding as an example, copper bumps are firstly formed on chips, and then chips are electrically connected to circuit boards through the copper bumps on the chips. However, owing to high risk of manufacturing copper bumps in wafer level, yield must be strictly controlled, and complexity of rework will directly response to the manufacturing cost and time.